The present invention relates to the cheese industry. It relates more particularly to composite cheese products comprising an external cheese paste also designated external shell and an internal filling having identical or different texture, the external cheese paste being composed of processed cheese.
It also relates to a process for the manufacture of such products.
Food products are known which comprise cheese pastes combined with other cheeses or cheese specialities or other food products.
In general, in the case of the combination of cheese pastes, distinct blocks of cheese are caused to adhere to each other or they are filled with different pastes by means of a binding agent used in the food industries.
There may be mentioned, by way of example, patents FR 2,411,539, FR 2,475,301 and FR 2,504,781 which describe cheeses made in several distinct and successive steps, formed of several layers of processed pastes.
In general, the external paste is a processed homogeneous paste which makes it possible to provide good mechanical strength to the finished product, and the manufacturing technique is that for a processed cheese.
The documents EP-A-102 232, EP-A-130 740 and EP-A-130 772 describe extrusion techniques which make it possible to produce marbled food products or food products comprising an external paste surrounding an internal paste.
However, the latter techniques which have been used are suitable for confectionery or for products based on flour and are not appropriate for cheese.
There is known, in addition, from the document EP-A-260 194, a process for the manufacture of composite products formed from a cheese paste forming a shell having a texture similar to that of the original product and of a second product forming a filling and enclosed in the shell.
This process comprises a first step of adding proteins to the cheese as well as a subsequent step of mechanically treating and of shaping the treated product. This process is however limited in its implementation, on the one hand, by the raw material used, which is a ripened pressed cheese having a dry extract (DE) of at least 50% and, on the other hand, by two distinct implementation steps.
There is also known from the document EP-A-358 983 a process for producing a composite cheese of which the outside consists of an acid or rennet drained fresh curd and the core consists of a fromage frais of a different nature to the coating so as to create a contrast in texture; the process used for producing this product is co-extrusion.
Furthermore, the document EP-A-727 138 describes the production, by co-extrusion, of a composite cheese product of which the outside is made by mixing, texturing and cooking the fresh curd and the core is made of cheese or another food product, so as to create a contrast in texture.
The document DE-A-128 963 indeed describes the production of composite cheeses comprising separate alternate layers, based on processed cheese, by a technique of metering in the hot state, the production of these products being carried out in several stages using an intermediate mold with walls which allow the different pastes to be delimited at the time of casting and the gelled product then being transferred into its final packaging. However, this process relates to products formed of several pastes in the form of separate layers or bands which are all based on processed cheese.
Moreover, the applicant has already described in patent FR 2,650,484 the production of a cheese-based composite product comprising a firm external shell and an internal paste having a softer consistency according to the so-called xe2x80x9cone-shotxe2x80x9d technique which consists in co-metering and co-molding two constituents which produce the shell and the filling respectively.
In this document, the external shell is made from a noncoagulated milk concentrate but which comprises a coagulating agent (rennet, acidifying agent) and it is at the co-molding time that the forming into a mass or gelling of the external shell occurs.
Thus, the process described makes it possible to obtain cheese shells from milk protein concentrates and not from processed cheese and the co-metering and co-molding are performed at low temperature (30 to 50xc2x0 C.).
In general, the processes used in the techniques cited above are either the successive casting, in the hot state, of different processed pastes in order to obtain superposed layers consisting of different products, or the co-extrusion which makes it possible to obtain products comprising a coating and a core of a different texture and/or nature. To date, the latter technique, which makes it possible to obtain products with coating and filling, is only performed on cold products. Indeed, co-extrusion on hot products has never been described or performed.
Moreover, the technique described does not make it possible, because of its characteristics (shearing), to obtain a coating in the form of a homogeneous and continuous gel. Indeed, its application to already gelled products would have the consequence of destroying the gel which would as a result no longer be continuous.
To date, no cheese product of the type comprising an external shell consisting of a homogeneous and continuous processed cheese gel and an internal filling consisting of processed cheese and optionally other food products, is consequently known.
The objective of the invention is to satisfy this demand. For that, a process for co-metering of the constituents, in the hot state, that is to say above the gelling temperature of the proteins, is used, followed by a static cooling which allows continuous gelling.
A second objective of the present invention is to provide a cheese-based composite product of the type comprising an external shell and an internal filling which is completely enclosed in the external shell, at least the external shell being based on a processed cheese.
Another objective of the present invention also relates to the process for the manufacture of a composite cheese of the abovementioned type.
The aim of the present invention was achieved by adapting the co-metering and co-molding technique described in FR-A-2,650,484 to a processed cheese paste for the production of the external shell, and by taking advantage of the specific properties of processed cheeses, in particular their creaming capacity which allows the passage from the sol state to the gel state.
The subject of the invention is thus a composite cheese product of the type comprising an external shell and an internal filling which is completely enclosed in the external shell, at least said external shell being obtained from a processed cheese with creaming capacity.
In the invention, the term xe2x80x9cprocessed cheesexe2x80x9d or xe2x80x9cprocessed cheese pastexe2x80x9d designates the product obtained by the processing, in the hot state, in the presence or otherwise of emulsifying salts, of cheeses and/or of other dairy products (butter, cream, milk powder, whey), or even of proteins and of fat of plant origin. Other additives (gelling agents, thickeners) may also be present in the formula.
The expression creaming capacity is understood to mean the property of processed cheeses to thicken under the action of the double phenomenon of:
peptization of the proteins allowing the hydration of the chains and resulting in the swelling of the medium and in the increase in viscosity; and
insertion of the Ca pyrophosphates formed during the heat treatment between the protein chains in order to form inter- and intraprotein ionic bonds causing the gelling of the network (Le fromage, A. Eck, J. C. Oillis, Ed. Lavoisier, Technique et documentation, 1997).
The filling may consist of a processed cheese paste or the like or of a food product of a different nature, in particular a puree.
Advantageously, the external shell and the internal filling are produced by co-metering and co-molding, in the hot state, of the processed cheese paste forming the external shell and of the food product forming the filling, the temperature used during these stages being greater than the gelling temperature of the processed cheese constituting the external shell.
The subject of the invention is therefore also a process for the manufacture of a cheese-based composite product of the type comprising an external shell and an internal filling completely enclosed in the external shell, and at least the said external shell being obtained from a processed cheese having creaming capacity, the process being characterized in that the co-metering of the constituents forming respectively the external shell and the filling is carried out in the hot state and in that said constituents are simultaneously introduced into a mold where they are cooled at least to a temperature of less than the gelling temperature of the processed cheese paste constituting the external shell.
Thus, the implementation of the process of the invention is based on the use of the specific properties of processed cheese, in particular its capacity to xe2x80x9ccreamxe2x80x9d allowing the passage from the SOL state to a GEL state.
The passage from the SOL state to the GEL state is performed during the cooling to a temperature of less than 50xc2x0 C. This cooling is performed in a static state, which makes it possible to obtain a continuous gel. It is carried out after metering into the packaging and shaping of the product.
In the context of the present invention, this change of state is desired for the formation of the external coating, but it will be optional for the central filling, in particular in the case where a xe2x80x9cflowingxe2x80x9d core of processed cheese is desired.
One of the essential characteristics of the invention is the carrying out of the co-metering in the hot state, which has two advantages:
1) The cheese is metered at a temperature greater than the gelling temperature of the proteins, that is to say when the product is in the SOL state, and it is during the cooling that it is converted to a GEL which fixes the shape; the metering temperature, which is greater than the gelling point of the products will be greater than 70xc2x0 C. and preferably between 70 and 90xc2x0 C.
2) The high temperature makes it possible to decontaminate the product and thus ensure good hygiene qualities and longer preservation.
The invention will be understood more clearly from the description which follows:
A processed cheese paste and a product intended to form the internal filling consisting of cheese or otherwise, are used as starting material, the constituents having a similar viscosity during the co-metering and the introduction into the mold. Thus, the constituent which forms the core or internal cheese may be processed cheese, processed fromage frais, fromage frais or alternatively food pastes of the puree type having, at the time of co-metering and introducing into the mold, a viscosity close to that of the processed cheese intended to form the external shell.
The expression similar viscosities is understood to mean that the components forming the external shell and filling have, during the simultaneous step of co-metering and introducing into the mold, a difference in viscosity of less than 30 poises (3 Paxc2x7s) under a shear of 150 sxe2x88x921.
This condition of similarity of the viscosity of the two pastes is particularly important at the time of introducing the two pastes into the mold in order to obtain a final product with two very distinct and non-mixed components.
At the time of the co-metering and introducing into the mold, the apparent viscosity of the two components is advantageously between 5 and 50 poises (0.5 to 5 Paxc2x7s) measured at 80xc2x0 C. under a shear of 150 sxe2x88x921.
Indeed, the apparent viscosity should not be too low because at this viscosity, the pastes would be too fluid and would mix with each other at the time of introducing into the mold; neither should it be too high because, in this case, the pastes would have a firmness which will be hardly compatible with the process of co-metering and introducing into the mold used simultaneously.
Moreover, at the time of the metering, the pastes advantageously have similar pH values. The pH of these two products is preferably between 5.0 and 5.8, acidic pH values (pH less than 4.5) not being highly desirable because of the destabilization of the product which would result therefrom.
The expression xe2x80x9csimilar pH valuesxe2x80x9d is understood to mean a difference in pH which is not greater than 0.5 units, at the temperature for co-metering and introducing the constituents into the mold.
In addition, the pastes advantageously have similar dry extracts.
The expression xe2x80x9csimilar dry extractsxe2x80x9d is understood to mean a difference not greater than 5% by weight.
This closeness of pH as well as that of dry extract are also important for the shape and the organoleptic qualities of the product to be well maintained during the preservation of the product.
The co-metering of the constituents is carried out at a temperature preferably of between 70 and 90xc2x0 C.